Alarm circuits are used to provide physical security for objects and spaces. One type of alarm circuit includes a base or control station to which one or more main electrical cables are electrically connected. The main cables extend from the base station to a point where they are physically connected by a security loop cable to an object or a gate. The gate typically governs entry to a secured space. The distal end portion of the main cable is mechanically and electrically connected to a security loop cable which is physically secured to the object or gate. Physical attachment of the security loop cable to the protected item is accomplished by threading a momentarily free end of the security loop cable through an opening in the object or gate and then looping the cable back toward itself where it is releasably fastened to either itself or the main cable or an extension of the main cable. The looped end portion of the security loop cable is sometimes referred to as a pigtail. With the pigtail looped around the object or gate, the object or gate cannot be moved without causing separation of the security loop from the remainder of the cable, thereby triggering the alarm circuit.
When authorized personnel need to move a secured object or open a secured gate they have to first deactivate the alarm circuit at the base station and then disconnect the security loop cable from the object or gate. In the case of a gate, once the authorized personnel pass through the gate it is reclosed, the security loop cable is reattached to the main cable and the alarm circuit is reactivated to resume protection of the gate.
If unauthorized parties attempt to move the object or gate, they will typically do so by either cutting the security cable or unfastening the security loop. The less skillful unauthorized parties won't even notice the cable and their attempt at forced movement of the object or gate will either unintentionally disconnect the security loop from the main cable or simply break one of the cables at some point. In any case, since either of these is done without deactivation of the alarm circuit, this break in the electrical continuity of the cable is sensed at the base station and triggers an alarm condition at the base station so that appropriate actions can be taken. Such actions include alerting security personnel so they can respond, turning on audible sirens, turning on lights, aiming a camera at the affected area, or some combination of these or related actions.
Economic considerations dictate that only a single main cable extends from the base station to the protected object or gate, although the single cable may have multiple insulated wires within it. Further, an alarm system of the type described requires selective fastening and unfastening of a security loop or pigtail at the end of the main cable such that the security loop can be selectively threaded through a gate or a portion of a protected object to prevent movement thereof without deforming the loop.
In the past the connectors for forming the security loop have been inadequate in several respects. Most notably they fail to disconnect reliably when under stress without damage to the connector. This comes into play because even conscientious authorized personnel have been known to forget to disconnect the security loop. When the gate or object is moved with the security loop still attached, it would be preferable for the security loop connector to disconnect without destroying either the connector or cable, i.e., it should disconnect in a safe, non-destructive manner. Of course, unless the alarm circuit was deactivated first, even a safe, non-destructive disconnection will still trigger an alarm. But with a safe, non-destructive disconnection, after all the tumult of a triggered alarm has been ironed out, authorized personnel can simply reconnect the security loop without repair or replacement.
It has also been found that in the past security loop connectors have unfortunately had the ability to confound authorized personnel as to their proper connection. Thus, attempts to reconnect the security loop fail to make the proper electrical connection, with the result that the base station cannot reset the alarm circuit and place it in operative mode. Aggravation over failed connections may eventually lead authorized personnel to make an unauthorized decision to stop using the alarm circuit altogether.